Shock absorber



J. B. KIRBY SHOCK ABSORBER atente ov. l

application ana narra readA sensi no. asie.

ToaZZ whomt' may concern." y Be it known that l, JAMEs'B. l?. is a citizen of the United States?,` residing at Cleveland, in the county of @Cuyahoga andl State of Ohio, have invented a certainnew.

and useful improvement in Shock Absorbet-s, of whichV they-following is a full, clear, and `.exact description,A reference being `had to the accompanying -drawin s. V y t t This invention relates to that cy assiof devices employed. for restraining the' encessively vio ent `movemr-rntsof vehicle. rin, especially those of automobiles, there rendering the movement of the vehicle body more comfortable and decreasing the danger of breaking the springs. Fliese devices have receivedl the somewhat inaocuratebut well understood 4name of shock absorbers. 'l`he particular Aclass of such devices to which this invention belongs is that wherein the' relative movement of the parts is restrained or retarded by the movements of a :duidenclos'ed in a casing, and* the main object 'of the invention is the provision ofa .deviceof f l this characterwherein the movement of the fluid sha ll be restrained toan extent which depends upon the violencel of. the shock which creates such` movement. IOther objects of the invention are the provision of a device of this character which shall be extremely simple, compact, of few partsand easily attached to the machine.; the provision of a shock. absorber which shall oi'l'er the same character of action at all times regardless of the initial weightcarried bythe 'vehicle, which shall be unresponsive to minor blows and to all gentle movement. ofthe springs, but responsive to all the severer shocks; which shall oller no resistance to the t0 downward movement of the body and only a proportional resistance to the upward movement thereof; while further objects and advantages of the invention will .become apparent as the description proceeds.

` In' vthe-drawings accompanying and forming a part of thisapplication l haveshown a preferred embodiment of my invention together with its mode ofappIicatiOn to the y rearward part of an automobile, although it will. be understood that a great many changes can be made in details of construction. and that the device is equally applicable tothe front axle aste the `rear axle; ln

`these drawings Fig. l is a perspective view' of my improved shock absorber showing threading that portion of the is the valve seat 35 which carries mode of attachment to al1-automobile; Figs. 2 and 3 arev vertical sectional viewscorrespending to the lines 2--2 andai-3, respec-I tively, of Figs. et, 5 and 6'; Figs. Il, 5 and 6 are horizontal sectional viewscorresponding to the lines M, 5--5 and @-6, respectively, l of Figs. 2 and 3; and Fig. 7 illustrates a modified form of device.

Describing the parts by'v reference characters, my lmproved shock t w .comprises a'hollo'w metal casing lhaving suitable attaching ears 2-2 and a ovable top "3, the *rearward'facei of the casing ling made flat to facilitate 'its attachment to a suitable part of the "automobile body, such 'T0 as the spring hanger 4. `Journaled transverselyof the upper partlof this casing is a horizontalrock-shaft 5 carryin an arm 6 whose outerI end isconnected to t e axle 7 b y suitable means'sueh as the rigid'linlc 8. the 75 latter `preferably having ball joints 9-9 at itsA en so that universal movement may exist. l

e One side of the casing contains the well ll and the opposite side contains the `*vertical cylinder l2 provided with the piston 13, connected by means of the piston rod ld, to the 4free end of an operating arm l5 whose opposite end is attached to the ,rock shaft. Leading laterally from the lower part of .this cylinder arc two passageways, 20 and 21, which communicate fwth'the well 1l by means of ducts 22, 23, respectively. 'lhe passageway 2O is preferably made by drill-1V ing horizontally into the bottom of the cyl- De inder from the outside of the casing so as to intersect the duct 22,` and afterwards n assageway wlnch `lies outside said duct as s iown at 25.

ll then insert in said threaded portion the apertured plug 26 in which slidably mounted the stem 27 having at its inner end the integral conical head28 and at its outer end the removable Hathead 29. Press# ing against the latter'head is the spring 30 100 and outside of the spring is the screw plug 3l, which serves the double purpose of closing the bore and adjusting the `tension of said spring. Threaded in the other duct 23 e d1 the down- 165 war y opemng, rin s a et valve 36 whose stem pl risgesp into the 'lhe valvehead 28 is formed with its larger end innermost and of such'a size as to 'passloosely through the passageway 20,` and ,110

Vmi

is normally supported a short distance inside ofthe end of said passageway as shown in Figs.2and 6. The casing is filled with any suitable non-freezing liquid, preferably a good lubricating oil. Upon increasing or 'decreasing the weight in the car, the parts will assume without obstruction the relative position determined by the stiffness of the vehicle spring, and in the operation of the vehicle the normal slow or gentle action of the spring can occur without opposition, the oil having a free movement into the cylinder through both of the passageways and having a free movement out of that cylinder through the passageway 20 so long as its movement is slow. Also in case the Wheels shall strike an obstruction which throws them upwardly suddenly towards the body, or in case the body shall acquire a` down# ward movement relatively to the axle, the resulting upward movement of the piston 13 occurs without opposition, regardless of the violence, the valve 36 opening for the purpose; but any severe upward movement of the body relatively to the Wheels, whichl is the kind of movement that causes breakage of springs, discomfort to passengers and injury 4tolloads, causes such a rush of fluid past the valve 28 as to draw it outwardly towards its 4seat and thereby restrict the area of the liquid passage by Aan amount which is proportional to the pressure. Sufficient leakage is provided, either around the valve 28 or around the piston 13 or by apertures in the parts, to permit a slow return of the oil to the well 11 even though the valve 28 be forced to its position of extreme closure. In this way the parts are enabled to resume slowly their original positions ready to cushion the next blow, and the amount of cushioning eect is at all times substantially p proportional to the violence ofthe jolt.

In the construction shown in Fig. 7 the passageway 21 and its valve are omitted and onl a single passageway 2Oa employed, which is larger and cylindrical and opens into the well 11 by a port 40 controlled by a sliding valve 41 formed inA its side with a tapering port 42. This valve is normally held inwardly by the li ht spring 43, and when displaced outward y a given distance comes into contact with a second spring 44 Whose tension is adjusted by the screwk45, The ports 40, 42 are tapered so as torestrict the fluid movement at the proper rate, and are large enough to admit fluid to the cylinder at a suiiiciently high rate for all reasonable spring speeds and above this point some restraint 1s not amiss. Upon an upward movement of the body the valve 41 first moves sufiiciently far to contact with the spring 44, even with a comparatively gentle movement, and thus closes the port sulliciently to ali'ord a considerable restriction of fluid movement in case the pressure of the latter be sufficiently great to move the valve past this point.

It will be understood that many variations in design, arrangement and construction of the various arts and numerous substitutions of equiva ents for the parts themselves can be made within the scope of my invention wherefore I do not restrict myself in any way except as specifically set forth in the claims hereto annexed.

Having thus described my invention, what I claim is:

1. In a device of the character described, in combination, a fluid-containing casing having a well and a cylinder therein, there being two passageways between said cylinder and well, a piston in said cylinder, a valve in one of said passageways adapted to permit free movement of fluid from said lwell to said cylinder, and a valve in the other passageway adapted to permit a restricted movement of fluid from said cylinder to said well, said last valve being normally open and arranged to close in the direction of fluid movement.

2. In a device of the character described, in combination, a fluid-containing casing havingV a well and a cylinder therein, there being two passageways between said cylinder and well, a piston in said cylinder, a valve in one of said passageways adapted to 1permit free movement of fluid from said wel to said cylinder, anormally open valve in the other passageway adapted to close upon movement of fluid outwardly from said cylinder toward said well and to restrict such passageway in roportion to such movement, and an adjusta le spring tendin to oppose the closing movement of sai valve.

3. In a device of the character described, in combination, a fluid-containing casing having a well and a cylinder therein, there being two passageways between said cylinder and well, a piston in said cylinder, and a spring pressed valve in each passageway both of which open toward the cylinder, the spring of one valve acting at all times to keep 1t closed and that of the other to keep it open.

4. In a device of the character described, in combination, a casing having a well and a cylinder therein, a piston in said cylinder, and -a plurality of passageways between said well and the portion of said cylinder at one end of said piston, an inwardly opening, spring-seated, inlet valve in one passageway, and an inwardly-opening, spring-o ened, outlet valve in another passageway a apted. to be displaced outwardly by the movement of fluid therepast and when so displaced to obstruct its passageway by an amount which is substantially proportional to its displacement.

wiaeee 5. ln a device of the character described, in combination, a fluid-containing casing adapted to be attached to one part of an automobile and having therein a well and a cylinder, means establishing communication between said cylinder and well, a piston in said cylinder and operatively connected to a relatively movable part of the automobile, and means for restricting the flow of fluid from said cylinder to said well by an amount which varies directly with the speedof the piston movement and is independent of the extent of such movement.

6. ln a device of the character described, in combination, a fluid-containing casing adapted to be attached to one part of an automobile and having therein a well and a cylinder, a piston in said cylinder operatively connected to a relatively movable part of the automobile, one end of said cylinder being in open communication with said well,

means for permitting the movement of Huid between the opposite end of said c linder and well substantially unim eded so ong as its rate of movement is smal and means operative when the pressure inside the lastnamed end of said cylinder rises to a. predetermined point for restricting the outflow therefrom by an amount which is proportional to that pressure.

7. In a device of the character described, in combination, a fluid-containing casing adapted to be attached to one part of an automobile and having therein a well and a outwardly, said valve being arranged -to restrict the opening through the passageway by an amount increasing with such outward movement.

8. lln a device for restraining the relative movement between two spring-connected members of a vehicle, in combination, a liquid containing casin adapted to be secured to one of the vehic e members, a movable displacing member therein and fitting the walls thereof so as to separate the same into a pressure chamber and a storage chamber, means for securing said displacing member to the other vehicle-memmr, there being a passa eway extending from one chamber to `the ot er, a valve operatively associated with said passagewa and a spring normally holding said va ve open wh' e permitting 1t to approach its seat the same by an amount which is at all times proportional to the' eX- -cess of pressure existing in the pressure chamber over that in the storage chamber.

In testimony whereof, I hereunto aiiix my signature.

S B. KlRBY. 

